IBM TOTALSTORAGE DS4500 - Manual (Page 7)

Drive Loop A
Drive Loop B
Drive Loop D
Drive Loop C
Input Input Output Output
First DS4000 drive
enclosure
Last DS4000 drive
enclosure
New DS4000 drive
enclosure
DS4500 Storage
Subsystem
ESMs
First DS4000 drive
enclosure
Last DS4000 drive
enclosure
Storage Expansion
Enclosures - Group 1
Storage Expansion
Enclosures - Group 2
ds454min
Figure 5. Redundant drive loop cabling overview — four mini hubs
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